1. Inclined to tolerate the beliefs or behavior of others; forbearing: a tolerant attitude.
2. Able to withstand or endure an adverse environmental condition: plants tolerant of extreme heat.
3. Able to digest or metabolize a food, drug, or other substance or compound: people who are lactose tolerant.
[French tolérant, from Latin tolerāns, present participle of tolerāre, to bear; see TOLERATE.]
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Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.